Works on Mr Robot S3 Ep8. The series is usually in 16:9 but this ep. is in 21:9. With black bars. So Amazon does not natively crop the video.

However once you rewind the video, half of the screen jumps up and the top half of the video becomes cropped. Great(!)

Pressing Z twice fixes it though. But this is a hassle. Would be great if the add on did this itself.

Update: Wow thanks for the reply dev! I only wrote the review for others in a similar situation but am happily surprised you replied!

Amazon support isn't really needed. Normally, 21:9 videos on Amazon automatically take up the whole screen without black bars. Mr Robot however is filmed in 16:9. The episode in question is also 16:9. Near the beginning however, it becomes 21:9 by adding black bars to the top and bottom. This is part of the story since the viewer is put into the shoes of a character who is in a cinema. It's the kind of thing Mr Robot does to viewers - by putting people in someone's shoes and changing the context within which they are in. So several minutes of the Ep do not have black bars.

I would attach a pic but it does not let me here.

I would suggest borrowing someone's Amazon Prime account or getting a 1 month trial and watching parts of this episode to see it in action. Though again, I think you'd be better off putting attention in other areas unless this happens on other websites as well. Amazon does afterall normally stream 21:9 videos without black bars.